Correction for 'High-precision measurement of Cd isotopes in ultra-trace Cd samples using double spike-standard addition MC-ICP-MS' by Hui Chang
et al.
,
J. Anal. At. Spectrom.
, 2023,
38
, 950-962,
...https://doi.org/10.1039/D3JA00047H
.
Isotope ratios of heavy elements vary on the 1/10000 level in high temperature materials, providing a fingerprint of the processes behind their origin. Ensuring that the measured isotope ratio is ...precise and accurate depends on employing an efficient chemical purification technique and optimised analytical protocols. Exploiting the disparate speciation of Cu, Fe and Zn in HCl and HNO3, an anion exchange chromatography procedure using AG1‐×8 (200–400 mesh) and 0.4 × 7 cm Teflon columns was developed to separate them from each other and matrix elements in felsic rocks, basalts, peridotites and meteorites. It required only one pass through the resin to produce a quantitative and pure isolate, minimising preparation time, reagent consumption and total analytical blanks. A ThermoFinnigan Neptune Plus MC‐ICP‐MS with calibrator‐sample bracketing and an external element spike was used to correct for mass bias. Nickel was the external element in Cu and Fe measurements, while Cu corrected Zn isotopes. These corrections were made assuming that the mass bias for the spike and analyte element was identical, and it is shown that this did not introduce any artificial bias. Measurement reproducibilities were ± 0.03‰, ± 0.04‰ and ± 0.06‰ (2s) for δ57Fe, δ65Cu and δ66Zn, respectively.
Les rapports isotopiques des éléments lourds varient au niveau de la quatrième décimale dans les matériaux de haute température, fournissant ainsi un accès aux processus ayant participé à la formation de ces derniers. S'assurer que le rapport isotopique mesuré est précis et exact dépend de l'emploi d'une technique de purification chimique efficace et de protocoles analytiques optimisés. L'exploitation de la spéciation différentielle de Cu, Fe et Zn dans l'HCl et le HNO3 a permis le développement d'une procédure de chromatographie échangeuse d'anions utilisant de la résine anionique AG1‐X8 (200–400 mesh) et des colonnes en téflon (0.4 x 7 cm) pour séparer ces éléments à la fois les uns des autres mais aussi de ceux de la matrice dans des roches felsiques, des basaltes, des péridotites et des météorites. Il n'a fallu qu'un seul passage dans la résine pour produire un isolat mono élémentaire ultra pur, en minimisant le temps de préparation, la consommation de réactif et le blanc analytique total. En utilisant un MC‐ICP‐MS ThermoFinnigan Neptune plus, une alternance standard‐échantillon avec étalon externe a servi à corriger le biais de masse. Le Nickel était l'élément externe dans les mesures de Cu et de Fe alors que le Cu a été utilisé pour corriger les isotopes du Zn. Ces corrections ont été apportées en supposant que le biais de masse pour le spike et l'élément analysé était identique, et il est démontré que cela n'a pas introduit de biais artificiel. La reproductibilité des mesures a été de ± 0.03‰, ± 0.04‰ et ± 0.06‰ (2s) pour respectivement δ57Fe, δ65Cu et δ66Zn.
Nuclear Data Sheets for A = 133 Khazov, Yu; Rodionov, A.; Kondev, F.G.
Nuclear data sheets,
04/2011, Letnik:
112, Številka:
4
Journal Article
Recenzirano
Evaluated nuclear structure and decay data for all nuclei within the A=133 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum ...numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by S. Raab (1995Ra12), published in
Nuclear Data Sheets
75, 491 (1995).
A solid introduction to stable isotopes that can also be used as an instructive review for more experienced researchers and professionals. The book approaches the subject from the perspective of ...ecological and biological research, but its concepts can be applied within other disciplines.
Nuclear structure data pertaining to all nuclei with mass A=168 (Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt) have been evaluated and incorporated into the ENSDF data file. This evaluation ...supersedes the previous publication (V.S. Shirley,
Nuclear Data Sheets 71, 261 (1994) (literature cutoff date July 1993)) and subsequent ENSDF file revisions for Tb and Dy (C. Baglin, literature cutoff date of 15 June 1999) and Hf (B. Singh, literature cutoff date of 30 April 2001), and includes literature available by 15 June 2010. Since the above evaluations, the first excited states in
168Pt have been identified (1998Ki20, 2009Go16) and
α decay from
172Hg has been observed (2009Sa27, 2004Ke06, 1999Se14). New levels in
168Dy have been excited using the
170Er(
82Se,
84Kr
γ) reaction (2010So03). (HI,xn
γ) studies have significantly expanded our knowledge of level structure in
168Lu (1999Ka17, 2002Ha33),
168Ta (2008QiZZ),
168Yb (1995Fi01),
168Tm (2007CaZW),
168Hf (2009Ya21),
168Os (2001Jo11, 2009Od02) and, for
168Tm, important information has come also from (d,2n
γ) and (
α,n
γ) reactions (1995Si20). Revised decay schemes are available following new studies of
168Hf
ε decay (6.7 min) (1997Ba26),
168Lu
ε decay (1999Ba65),
168Ta
ε decay (2007Mc08) and
172Au
α decay (2009Ha42). Significant new information for
168Er is available from (p,t) (2006Bu09), (d,p) and (t,d) (1996Ma50), (
γ,
γ′) (1996Ma18), (136Xe, X
γ) (2010Dr02), (
238U,
238
U
′
γ
) (2003Wu07) and (n,
n
′
γ) (1998Be20, 1998Be62) reactions, and the availability of
γγ coin data (1994Ju02, 1996Gi09) for the (n,
γ) E=thermal reaction has resulted in some significant level scheme revisions.
Within the last decade, the high and continuing demand for precious and base metals, as well as critical elements, has prompted a global rush on a scale never before seen. This eventually resulted in ...the demand for considerable innovation and improvement in mineral deposit genetic modelling and ore formation regimes for the many different types of gold deposits, now recognized, and paralleled by the wide employment of exploration techniques and a rapid expansion of geological databases.
This Special Issue will show case studies of porphyry polymetal systems, orogenic gold formations, water–rock reaction, ore-forming structure evolution, mineralogy and petrology of ore deposit, ore formation regime, geochronology and geochemistry of ore deposit, ore-forming evolution, mineral exploration and cutting-edge technology in ore deposit study.
The slow neutron capture process in massive stars (weak s process) produces most of the s-process isotopes between iron and strontium. Neutrons are provided by the {sup 22}Ne(alpha,n){sup 25}Mg ...reaction, which is activated at the end of the convective He-burning core and in the subsequent convective C-burning shell. The s-process-rich material in the supernova ejecta carries the signature of these two phases. In the past years, new measurements of neutron capture cross sections of isotopes beyond iron significantly changed the predicted weak s-process distribution. The reason is that the variation of the Maxwellian-averaged cross sections (MACS) is propagated to heavier isotopes along the s path. In the light of these results, we present updated nucleosynthesis calculations for a 25 M{sub sun} star of Population I (solar metallicity) in convective He-burning core and convective C-burning shell conditions. In comparison with previous simulations based on the Bao et al. compilation, the new measurement of neutron capture cross sections leads to an increase of s-process yields from nickel up to selenium. The variation of the cross section of one isotope along the s-process path is propagated to heavier isotopes, where the propagation efficiency is higher for low cross sections. New {sup 74}Ge, {sup 75}As, and {sup 78}Se MACS result in a higher production of germanium, arsenic, and selenium, thereby reducing the s-process yields of heavier elements by propagation. Results are reported for the He core and for the C shell. In shell C-burning, the s-process nucleosynthesis is more uncertain than in the He core, due to higher MACS uncertainties at higher temperatures. We also analyze the impact of using the new lower solar abundances for CNO isotopes on the s-process predictions, where CNO is the source of {sup 22}Ne, and we show that beyond Zn this is affecting the s-process yields more than nuclear or stellar model uncertainties considered in this paper. In particular, using the new updated initial composition, we obtain a high s-process production (overproduction higher than {sup 16}O, {approx}100) for Cu, Ga, Ge, and As. Using the older abundances by Anders and Grevesse, also Se, Br, Kr, and Rb are efficiently produced. Our results have important implications in explaining the origin of copper in the solar abundance distribution, pointing to a prevailing contribution from the weak s-process in agreement with spectroscopic observations and Galactic chemical evolution calculations. Because of the improvement due to the new MACS for nickel and copper isotopes, the nucleosynthesis of copper is less affected by nuclear uncertainties compared to heavier s-process elements. An experimental determination of the {sup 63}Ni MACS is required for a further improvement of the abundance prediction of copper. The available spectroscopic observations of germanium and gallium in stars are also discussed, where most of the cosmic abundances of these elements derives from the s-process in massive stars.
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